Gas turbine assemblies and methods

ABSTRACT

The systems and methods described herein relate to a dome of a gas turbine assembly configured to suppress pressure pulsations. The systems and methods provide a dome having an aperture configured to surround an injector assembly of a combustor. The dome having a front panel extending radially from the aperture. The systems and methods couple a first cavity to the front panel. The first cavity includes a series of ducts. A first duct of the series of ducts is configured to receive airflow into the first cavity from a compressor and a second set of ducts of the series of ducts and a third duct of the series of ducts are configured to direct airflow to the combustor from the first cavity, wherein the third duct has a larger diameter than the second set of ducts.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Divisional of U.S. patent application Ser. No.15/714,118 filed Sep. 25, 2017, currently pending, which is herebyincorporated in its entirety herein.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

The United States Government retains license rights in this inventionand the right in limited circumstances to require the patent owner tolicense others on reasonable terms by the terms of Government ContractNo. DTFAWA-15-A-800013.

FIELD

The subject matter described herein relates to a dome of a gas turbineassembly configured to suppress pressure pulsations.

BACKGROUND

A combustor of a conventional gas turbine assembly receives pressureperturbations or pulsations caused by a feedback loop between flowperturbations and unsteady heat release. The pressure pulsations causestructural and flow vibrations, which damage components of the gasturbine assembly. The damage caused by the pressure pulsations reduces alife span of the gas turbine assembly. Conventional methods to reducethe pressure pulsations have focused on determining and eliminating asource of the pressure based on the unsteadiness of the heat release ofthe gas turbine assembly. However, the conventional methods do noteliminate the pressure fluctuation completely and a direct damping ofsource pressure or hear release fluctuation is needed.

BRIEF DESCRIPTION

In an embodiment, a system (e.g., gas turbine assembly) is provided. Thesystem includes a dome having an aperture configured to surround aninjector assembly for a combustor. The dome having a front panelradially extending from the aperture, and have a first cavity thatincludes a series of ducts. A first duct of the series of ducts isconfigured to receive airflow into the first cavity from a compressor,and a second set of ducts of the series of ducts and a third duct of theseries of ducts are configured to direct airflow to the combustor fromthe first cavity. The third duct having a larger diameter than thesecond set of ducts.

In an embodiment, a method (e.g., for suppressing pressure pulsations ofa gas turbine assembly) is provided. The method includes providing adome having an aperture configured to surround an injector assembly fora combustor. The dome having a front panel extending radially from theaperture. The method includes coupling a first cavity to the frontpanel. The first cavity includes a series of ducts. A first duct isconfigured to receive airflow into the first cavity from the compressor.And a second set of ducts that are configured to direct an airflow toreduce a thermal temperature of the dome.

In an embodiment, a system (e.g., gas turbine assembly) is provided. Thesystem includes a front panel radially extending from an aperture thatsurrounds an injector assembly of the gas turbine assembly. The frontpanel having first and second cavities with the first cavity having afirst set of ducts configured to receive airflow into the first cavityfrom the compressor. A second set of ducts configured to direct airflowto a combustor. The second cavity having a third duct configured toreceive airflow into the second cavity and a fourth duct configured todirect airflow to a combustor. The fourth duct having a diameter largerthan the second set of ducts.

BRIEF DESCRIPTION OF THE DRAWINGS

The present inventive subject matter will be better understood fromreading the following description of non-limiting embodiments, withreference to the attached drawings, wherein below:

FIG. 1 illustrates an embodiment of a turbine assembly;

FIG. 2 illustrates a perspective view of an embodiment of a dome;

FIG. 3A illustrates a side view of a first cavity of the dome shown inFIG. 2 ;

FIG. 3B illustrates a side view of first and second cavities of the domeshown in FIG. 2 ;

FIG. 4 is a graphical illustration of a pressure pulsation of aconventional gas turbine assembly;

FIG. 5 illustrates a perspective view of an embodiment of a dome;

FIG. 6 illustrates a side view of the dome shown in FIG. 5 ;

FIG. 7 illustrates airflow of first and second cavities of the domeshown in FIG. 5 ;

FIG. 8 illustrate a perspective view of an embodiment of a dome;

FIGS. 9A-B illustrate a backside and a translucent view of the domeshown in FIG. 8 ;

FIG. 10 illustrates a perspective view of an embodiment of a dome;

FIG. 11 illustrates a side view of first and second cavities of the domeshown in FIG. 10 ;

FIG. 12 illustrates a perspective view of an embodiment of a dome;

FIG. 13 illustrates a side view of first and second cavities of the domeshown in FIG. 12 ; and

FIG. 14 illustrates a flowchart of a method for suppressing pressurepulsations of a gas turbine assembly, in accordance with an embodiment.

DETAILED DESCRIPTION

The systems and methods described herein relate to a dome of a gasturbine assembly configured to suppress pressure pulsations of acombustor. The dome is interposed between the combustor and thecompressor. The dome includes an aperture configured to surround aninjector assembly. The injector assembly provides fuel either gaseousand/or liquid fuel and an oxidizer, which produces a flammable mixtureof fuel and oxidizer. The dome includes a front panel radially extendingfrom the aperture. The front panel includes one or more cavities, whichinclude a series of ducts. The ducts enable the dome to perform dualfunctions of shaping and/or containing the reacting flow while alsosuppressing pressure pulsations generated by the combustor.

For example, a first cavity of the series of ducts receives airflow fromthe compressor into the cavity. The first cavity includes second andthird ducts of the series of ducts. The second ducts are configured todirect a portion of the airflow to reduce a thermal temperature of thedome. For example, the second ducts are configured to direct the airflowto a hot side of the dome, which decreases a temperature of the dome.

In another example, the dome includes first and second cavities. Thefirst and second cavities include different series of ducts. The firstcavity includes first and third of the series of ducts, and the secondcavity includes second of the series of ducts.

The second and third ducts have different sizes. Optionally, the thirdducts have a larger diameter relative to the second cavities.Optionally, a size and/or length of the third ducts and a size of thefirst cavity configured such that the resonance may be targeted at afrequency range of concern. The frequency range represents pressurepeaks of flow vibrations of the combustor. The size and/or length of thethird ducts and the size of the first cavity are optimized to dampen thepressure peaks at the frequency ranges. Optionally, the optimization mayconsider the bias flow level through the cavities. The bias flowcorresponds to an amount of air contained, an air pocket, within thefirst cavity. The increase in the amount of air contained in the firstcavity has the dual effect of broadening the acoustic absorption andpreventing hot gas ingestion.

At least one technical effect of embodiments described herein includemitigating pressure pulsations, which hamper operability and emissionperformance. At least one technical effect of embodiments describedherein include reducing the impact of a design cycle of the gas turbineassembly. At least one technical effect of embodiments described hereininclude replacing existing domes of gas turbine assemblies to regainentitlement performances on efficiency and/or emissions. At least onetechnical effect of embodiments described herein include dual use ofbias flow (e.g., airflow) for cooling and acoustic dampening of thedome.

FIG. 1 illustrates a turbine assembly 100 in accordance with anembodiment. The turbine assembly 100 includes an inlet 116 through whichair enters the turbine assembly 100 in the direction of arrow 150. Theair travels in a direction 150 from the inlet 116, through a compressor118, through a combustor 120, and through a turbine 122 to an exhaust124. A rotating shaft 126 runs through and is coupled with one or morerotating components of the turbine assembly 100. The compressor 118compresses incoming air to create a supply of compressed air.

The compressor 118 and the turbine 122 comprise multiple airfoils. Theairfoils may be one or more of blades 130, 130′ or guide vanes 136,136′. The blades 130, 130′ are axially offset from the guide vanes 136,136′ in the direction 150. The guide vanes 136, 136′ are stationarycomponents. The blades 130, 130′ are operably coupled with and rotatewith the shaft 26.

The combustor 120 burns fuel to produce a high-pressure, high-velocityhot gas, which is received by the turbine 122. The fuel is supplied tothe combustor 120 from an injector assembly that includes a fuel nozzlevalve. The injector assembly extends through an aperture of the dome110. The dome 110 is interposed between the compressor 118 and thecombustor 120. The fuel nozzle valve extends through the aperture and iscoupled to the combustor 120. The fuel nozzle valve is substantiallyconcentrically aligned with respect to the dome 110. The dome 110includes a mixer within the aperture. The mixer includes a set of vanes,which swirls the fuel with the compressed air from the compressor 118.The mixed fuel and air are delivered by the dome 110 and discharged intothe combustor 120.

FIGS. 2-3B, and 5-13 illustrate different embodiments of domes (e.g.,the dome 110) for the gas turbine assembly 100. The domes include atleast one cavity that receives compressed air from the compressor 118.The at least one cavity provides a cushion, which absorbs the pressurepulsations generated by the compressor 118. The at least one cavitydampens and/or suppresses the pressure pulsations.

FIG. 2 illustrates a perspective view of a dome 200, in accordance withan embodiment. The dome 200 includes an aperture 206 configured tosurround an injector assembly 212. The injector assembly 212 providesfuel to the combustor 120. For example, the injector assembly 212extends through the aperture 206. The dome 200 includes a front panel202 that radially extends from the aperture 206. The front panel 202includes a series of ducts that extend through the front panel 202 andterminate at a surface of the front panel 202. For example, the frontpanel 202 includes a second set of ducts 208 and a third set of ducts210 from the series of ducts. The series of ducts is positioned atdifferent radial positions along the front panel 202. The third set ofducts 210 are shown interposed between the second set of ducts 208. Forexample, the second set of ducts 208 are at an inner and outer radialposition of the front panel 202, which surround the third set of ducts210. The ducts in the series are configured to have different sizes. Forexample, a diameter of one of the third set of ducts 210 is larger thanthe diameter of one of the second set of ducts 208. Additionally oralternatively, a number of ducts of the second set of ducts 208 isgreater than a number of ducts of the third set of ducts 210.

In connection with FIG. 3A-B, the dome 200 includes differentembodiments of cavities. FIG. 3A shows the dome 200 having a firstcavity 302. The first cavity 302 includes the series of ducts to directairflow from the compressor 118 to the combustor 120.

FIG. 3A illustrates a side view 300 of the first cavity 302 of the dome200. The front panel 202 includes a backside 308. The front panel 202includes the first cavity 302 along the backside 308 of the front panel202. The first cavity 302 extends along a circumference of the backside308 of the front panel 202. For example, the first cavity 302 extendsalong the backside 308 of the front panel 202 to include the series ofducts.

The first cavity 302 includes a first set of ducts 304 of the series ofducts. The first set of ducts 304 are configured to direct airflowreceived from the compressor 118 into the first cavity 302. A portion ofthe received airflow is exhausted to the second set of ducts 208. Thesecond set of ducts 208 are configured to direct the portion of thereceived airflow to reduce a thermal temperature of the dome 200. Forexample, the second set of ducts 208 are configured to direct theportion of the received airflow to a hot side of the dome 200. The hotside of the dome 200 may correspond to a portion of the dome 200proximate to the combustor 120.

A remaining portion of the received airflow is directed through areceiving duct 306. The receiving duct 306 is configured to direct theremaining portion of the received airflow into the first cavity 302. Forexample, the receiving duct 306 provides air into the first cavity 302to create a pocket of air within the first cavity 302. The pocket of airof the first cavity 302 is configured as a damper to suppress thepressure pulsations generated by the compressor 118.

For example, compressed air is delivered to the combustor 120 throughthe mixer of the aperture 206. The combustor 120 generates pressurepulsations based on the received compressed air. The pocket of airwithin the first cavity 302 acts as a cushion, which absorbs thepressure pulsations generated by the compressor 118. For example, thefirst cavity 302 is configured to absorb the pressure pulsationsgenerated by the combustor 120 and reduce the pressure pulsations of thegas turbine assembly 100.

The first cavity 302 includes the third set of ducts 210. The second setof ducts 208 are positioned about the third set of ducts 210. Forexample, the second set of ducts 208 are positioned around the third setof ducts 210. The third set of ducts 210 are configured to directairflow to the combustor 120 from the first cavity 302. For example, thepocket of air is dispersed from the first cavity 302 through the thirdset of ducts 210 to the combustor 120.

FIG. 3B illustrates a side view 350 of the dome 202 having first andsecond cavities 302, 354 of the dome 200. The front panel 202 includesthe first and second cavities 302, 354 along a backside 308 of the frontpanel 202. The first and second cavities 302, 354 extend along acircumference of a backside 308 of the front panel 202. The first andsecond cavities 302, 354 include different series of ducts. The firstcavity 302, shown in FIG. 3B, includes a first set of ducts 304 of theseries of ducts. The first set of ducts 304 are configured to directairflow from the compressor 118 into the first cavity 302. The firstcavity 302 is configured to provide the pocket of air to dampen orsuppress the pressure pulsations generated by the combustor 120. Thefirst cavity 302 includes the third set of ducts 210. The third set ofducts 210 are configured to direct airflow to the combustor 120 from thefirst cavity 302. For example, the pocket of air is dispersed from thefirst cavity 302 through the third set of ducts 210 to the combustor120.

The second cavity 354 includes a fourth set of ducts 356 positioned atthe backside 308 of the front panel 202. The fourth set of ducts 356 isconfigured to receive airflow from the compressor 118 into the secondcavity 354. The received airflow is exhausted to the second set of ducts208. The second set of ducts 208 are configured to direct the receivedairflow to reduce a thermal temperature of the dome 200. For example,the second set of ducts 208 are configured to direct the receivedairflow to a hot side of the dome 200. The hot side of the dome 200 maycorrespond to a portion of the dome 200 proximate to the combustor 120.

Optionally, volumes of the first cavity 302 and/or the size of the setof third ducts 210 are configured for particular target frequencies.FIG. 4 is a graphical illustration of a pressure spectrum 402 with aconventional dome. For example, the conventional dome does not includethe first cavity 302, the third set of ducts 210, and/or the like. Thepressure spectrum 402 is shown for different frequencies (e.g., Hz) of ahorizontal axis. A vertical axis represents a pressure generated by thecombustor 120. The pressure spectrum 402 includes two pressure peaks410, 412. The pressure peak 410 occurs at a target frequency indicativeof a resonance of the combustor 120.

The dome 202 can be configured to reduce an amplitude of the pressurepeak 410. For example, the first cavity 302 can be configured to haveresonance frequencies to match the target frequency of the pressurespectrum 402 at the pressure peak 410. A volume of the first cavity 302and/or the size of the set of third ducts 210 of the first cavity 302can be configured to have a resonance frequency at the first targetfrequency. The resonance frequency of the first cavity 302 is based onthe volume of the first cavity 302 and/or the diameter and length of thethird duct 210. The length represents a length of the third set of ducts210 from the first cavity 302 to the surface of the front panel 202. Theresonance frequency of the first cavity 302 is proportional to an area(e.g., diameter) of the third ducts 210 over the volume of the firstcavity 302 and the length of the third ducts 210.

For example, the volume of the first cavity 302 is configured to be 12m³. The diameter of the third set of ducts 210 for the first cavity 302is configured to be 133 mm, and the length is configured to be 0.2 mm.Based on the volume and the size of the third set of ducts 210, thefirst cavity 302 has a resonance frequency of approximately 280 Hz.

The configured first cavity 302 and the third set of ducts 210 form thepressure pulsation waveform 401. For example, the configured firstcavity 302 and corresponding third set of ducts 210 have the resonancefrequency at the target frequency at the pressure peak 410. The pressurepulsation waveform 401 includes a pressure peak 408 at the targetfrequency. The configured first cavity 302 dampened an amplitude of thepressure peak 410 at ranges about the target frequencies. For example,the pressure peak 410 is reduced by a value 414 to from the pressurepeak 408.

FIG. 5 illustrates a perspective view of a dome 500, in accordance withan embodiment. The dome 500 includes the aperture 206 configured tosurround the injector assembly 212 (not shown in FIG. 5 ). The dome 500includes a front panel 502 radially extending from the aperture 206.Similar to the dome 200 (FIG. 2 ), the dome 500 includes the series ofducts on a surface of the front panel 502. For example, the front panel502 includes the second and third set of ducts 208, 210.

FIG. 6 illustrates a side view 600 of the dome 500. The front panel 502includes first and second cavities 602, 604 along a backside 606 of thefront panel 502. The first and second cavities 602, 604 extend along acircumference of the backside 606 of the front panel 502. In connectionwith FIG. 7 , the series of ducts direct airflow from the compressor 118to the combustor 120.

FIG. 7 illustrates airflow of the first and second cavities 602, 604 ofthe dome 500. At 710, the first cavity 602 receives airflow from thecompressor 118. For example, the first cavity 602 includes a first setof ducts 304 of the series of ducts. The first set of ducts 304 areconfigured to direct airflow from the compressor 118 into the firstcavity 602.

At 711, a portion of the received airflow is exhausted through thesecond set of ducts 208 to the combustor 120. A remaining portion of thereceived airflow is directed through a receiving duct 702. The receivingduct 702 is configured to direct the remaining portion of the receivedairflow into the second cavity 604. For example, the remaining portionof the received airflow delivered by the receiving duct 702 creates theair pocket within the second cavity 604. Similar to the first cavity302, the pocket of air of the second cavity 604 is configured as adamper to suppress the pressure pulsations generated by the compressor118.

At 712, the second cavity 604 includes the third set of ducts 210. Thethird set of ducts 210 are configured to direct airflow to the combustor120 from the second cavity 604. For example, the pocket of air isexhausted from the second cavity 604 through the third set of ducts 210to the combustor 120.

FIG. 8 illustrate a perspective view of an embodiment of a dome 800. Thedome 800 includes the aperture 206 and the front panel 802. The aperture206 is configured to surround the injector assembly (not shown). Thefront panel 802 includes the series of ducts. For example, the frontpanel 802 includes the second set of ducts 208 on the surface of thefront panel 802. The second set of ducts 208 are positioned along acircumference of the surface of the front panel 802. Additionally oralternatively, the third set of ducts 210 are positioned along a portionof the circumference of the front panel 802. For example, the third setof ducts 210 are positioned with respect to cavities (e.g., first andsecond cavities 902, 904 in FIGS. 9A-B) that are positioned at abackside 906 of the dome 800.

FIGS. 9A-B illustrate the backside 906 and a translucent view 908 of thedome 800. The front panel 802 includes the first and second cavities902, 904. The first and second cavities 902, 904 are discrete cavityvolumes having a radial length 912 and width 910. For example, the firstand second cavities 902, 904 extend along different portions of thecircumference of the backside 906 of the dome 800. The first and secondcavities 902, 904 are positioned at different radial positions on thebackside 906 of the front panel 802. The translucent view 908illustrates the radial positions of the first and second cavities 902,904 with respect to the third set of ducts 210. For example, the thirdset of ducts 210 are located at the corresponding first and secondcavities 902, 904. The first and second cavities 902, 904 arestationary. For example, the first and second cavities 902, 904 areconfigured to be stationary with respect to the third set of ducts 210.Additionally or alternatively, a portion of the second set of ducts 208are positioned within the corresponding first and second cavities 902,904.

The first and second cavities 902, 904 include the first set of ducts304. The first set of ducts 304 can be positioned at different locationsof the first and second cavities 902, 904. For example, the first set ofducts 304 are positioned at a bottom position of the first cavity 902.In another example, the first set of ducts 304 are positioned at abackside of the second cavity 904. Optionally, the first set of ducts304 may be positioned along the inner radius of the first and/or secondcavities 902, 904 proximate to the aperture 206. The first set of ducts304 are configured to direct airflow from the compressor 118 into thefirst and second cavities 902, 904. A portion of the received airflow isexhausted through the second set of ducts 208 to the combustor 120. Aremaining portion of the received airflow remains within the first andsecond cavities 902, 904 forming the pocket of air. The pocket of air isdispersed from the first and second cavities 902, 904 throughcorresponding third set of ducts 210 to the combustor 120.

Optionally, volumes of the first and second cavities 902, 904 and/or thesize of the set of third ducts 210 are configured for particular targetfrequencies. In connection with FIG. 4 , the first and second cavities902, 904 and/or the size of the set of third ducts 210 can be configuredfor different target frequencies. The pressure spectrum 402 includes twopressure peaks 410, 412. The pressure peaks 410, 412 occur at targetfrequencies indicative of a resonance of the combustor 120. For exampleonly, a first target frequency is proximate to 861 Hz, and a secondtarget frequency is proximate to 1140 Hz.

The dome 800 can be configured to reduce an amplitude of the pressurepeaks 410, 412. For example, the first and second cavities 902, 904 canbe configured to have resonance frequencies to match the first andsecond target frequencies of the pressure spectrum 402. A volume of thefirst cavity 902 and/or the size of the set of third ducts 210 of thefirst cavity 902 can be configured to have a resonance frequency at thefirst target frequency. The resonance frequency of the first cavity 902is based on the volume of the first cavity 902 and/or the diameter andlength of the third duct 210. The length represents a length of thethird set of ducts 210 from the first cavity 902 to the surface of thefront panel 802. The resonance frequency of the first cavity 902 isproportional to an area (e.g., diameter) of the third ducts 210 over thevolume of the first cavity 902 and the length of the third ducts 210.

The configured first and second cavities 902, 904 and the third set ofducts 210 form the pressure pulsation waveform 404. For example, theconfigured first cavity 902 and corresponding third set of ducts 210have the resonance frequency at the first target frequency, and theconfigured second cavity 904 and corresponding third set of ducts 210have the resonance frequency at the second target frequency. Thepressure pulsation waveform 404 includes pressure peaks 408, 406 at thefirst and second target frequencies. The configured first cavity 902dampened an amplitude of the pressure peak 410 at ranges about thetarget frequencies. For example, the pressure peak 410 is reduced by avalue 414 to from the pressure peak 408. The configured second cavity904 dampened an amplitude of the pressure peak 412 at ranges about thetarget frequencies. In another example, the pressure peak 412 is reducedby a value 416 to form the pressure peak 406.

Optionally, the dome 800 may include only the first cavity 902 and/orboth the first and second cavities 902, 904 are configured to have acommon resonance frequency.

FIG. 10 illustrates a perspective view of an embodiment of a dome 1000.The dome 1000 includes the aperture 206 and a front panel 1002. Theaperture 206 is configured to surround the injector assembly (notshown). The front panel 1002 includes the third set of ducts 210 on thesurface of the front panel 1002. The third set of ducts 210 arepositioned along a circumference of the front panel 1002. The second setof ducts 208 are positioned behind a lip 1108 of the front panel 1002 asshown in FIG. 11 .

FIG. 11 illustrates a side view 1100 of first and second cavities 1102,1103 of the dome shown 1000. The first and second cavities 1102, 1103extend along a circumference of a backside 1110 of the front panel 1002.The first cavity 1102 includes the third set of ducts 210 and fourth setof ducts 1104. The fourth set of ducts 1104 are configured to directreceived airflow from the compressor 118 into the first cavity 1102. Thereceived airflow from the fourth set of ducts 1104 form the pocket ofair within the first cavity 1102. For example, the pocket of air isconfigured to dampen or suppress the pressure pulsations generated bythe compressor 118. The pocket of air within the first cavity 1102 actsas a cushion, which absorbs the pressure pulsations generated by thecompressor 118.

The second cavity 1103 includes a first set of ducts 1106 configured todirect received airflow from the compressor 118 into the second cavity1103. The second set of ducts 208 are configured to direct the receivedairflow to reduce a thermal temperature of the dome 1000. For example,the second set of ducts 208 are configured to direct the receivedairflow to a hot side of the dome 200 via the lip 1108. The lip 1108 ofthe front panel 1002 is angled to direct the airflow of the second setof ducts 208 away from the aperture 206 to the combustor 120.

FIG. 12 illustrates a perspective view of an embodiment of a dome 1200.The dome 1200 includes the aperture 206 configured to surround theinjector assembly 212, which extends through the aperture 206. The dome1200 includes a front panel 1202 radially extending from the aperture206. The dome 1200 includes a series of ducts on a surface of the frontpanel 1202. For example, the front panel 1202 includes the second andthird set of ducts 208, 210.

FIG. 13 illustrates a side view 1300 of first and second cavities 1302,1304 of the dome 1200. The front panel 1202 includes the first andsecond cavities 1302, 1304 along a backside 1408 of the front panel1202. The first and second cavities 1302, 1304 extend along acircumference of a backside 1308 of the front panel 1202.

The first cavity 1302 includes a first set of ducts 1301 of the seriesof ducts. The first set of ducts 1301 are configured to direct airflowfrom the compressor 118 into the first cavity 1302. The received airflowis exhausted through the second set of ducts 208 to the combustor 120.

The second cavity 1304 includes a fourth set of ducts 1306 positioned atthe backside 1308 of the front panel 1202. The fourth set of ducts 1306is configured to receive airflow from the compressor 118. The secondcavity 1304 is configured to provide the pocket of air to dampen orsuppress the pressure pulsations generated by the combustor 120. Thesecond cavity 1304 includes the third set of ducts 210. The third set ofducts 210 are configured to direct airflow to the combustor 120 from thesecond cavity 1404. For example, the pocket of air is dispersed from thesecond cavity 1304 through the third set of ducts 210 to the combustor120.

FIG. 14 illustrates a flowchart of a method 1400 for suppressingpressure pulsations of the gas turbine assembly 100, in accordance withan embodiment. The method 1400, for example, may employ structures oraspects of various embodiments (e.g., systems and/or methods) discussedherein. In various embodiments, certain steps (or operations) may beomitted or added, certain steps may be combined, certain steps may beperformed simultaneously, certain steps may be performed concurrently,certain steps may be split into multiple steps, certain steps may beperformed in a different order, or certain steps or series of steps maybe re-performed in an iterative fashion. In various embodiments,portions, aspects, and/or variations of the method 1400 may be used asone or more algorithms to direct hardware to perform one or moreoperations described herein. Optionally, the method 1400 may be utilizedto retrofit a conventional gas turbine assembly. For example, the method1400 is used to replace an existing dome of the conventional gas turbineassembly.

Beginning at 1402, providing a dome (e.g., the dome 200, 400, 500, 1100,1300) having the aperture 206 to surround the injector assembly 204 forthe combustor 120. For example, the dome 200 includes the aperture 206,which is configured to surround the injector assembly 204. The dome 200includes the front panel 202 extending radially from the aperture 206.

At 1404, coupling a first cavity to a front panel. For example, thefirst cavity 302 is coupled to the front panel 202 of the dome 200. Thefirst cavity 302 includes the series of ducts, which included on asurface of the front panel 202. For example, the second and third setsof ducts 208, 210 are positioned radially on the surface of the frontpanel 202. The first cavity 302 includes a first set of ducts 304 thatreceive airflow into the first cavity 302 from the compressor 118. Thefirst cavity 302 includes the second set of ducts 208 configured todirect a portion of the airflow to the combustor 120. The portion of theairflow directed by the second set of ducts 208 are configured to reducethe thermal temperature of the dome 302. For example, the second set ofducts 208 are configured to direct the portion of the received airflowto a hot side of the dome 200. The hot side of the dome 200 maycorrespond to a portion of the dome 200 proximate to the combustor 120.The remaining portion of the airflow enters into the first cavity 302forming the air pocket. The air pocket is configured to provide acushion, which is utilized to dampen and/or suppress the pressurepulsations generated by the combustor 120. The first cavity 302 includesthe third set of ducts 210. The third set of ducts 210 are configured todirect exhaust the air pocket from the first cavity 302 to the combustor120. For example, the third set of ducts 210 is configured to directairflow to the combustor 120 from the first cavity 302.

At 1406, if one or more target frequencies are present. For example, theone or more target frequencies are indicative of resonance frequenciesof the combustor 120. In connection with FIG. 4 , the one or more targetfrequencies represent pressure peaks 410, 412 of the pressure pulsationwaveform 402. The one or more target frequencies correspond tofrequencies that include the pressure peaks 410, 412.

If there are one or more target frequencies, then at 1408, the firstcavity and/or the third set of ducts are configured based on the one ormore target frequencies. For example, the first and second cavities 902,904 (FIG. 9A-B) and the corresponding size of the third set of ducts 210can be configured based on the one or more target frequencies. Thevolumes of the first and second cavities 902, 904 of the dome 800 andthe corresponding size of the third set of ducts 210 can be configuredsuch that the resonance frequency of the first and second cavities matchthe one or more target frequencies. The resonance frequency of the firstand second cavities 902, 904 are based on the volume of the cavities902, 904 and/or the size of the third set of ducts 210.

At 1410, dampening the pressure pulsations of the combustor 120. Forexample, the first cavity 302 contains a pocket of air provided by thefirst set of ducts 306. The pocket of air of the second cavity 604 isconfigured as a damper to suppress the pressure pulsations generated bythe compressor 118.

In an embodiment, a system (e.g., gas turbine assembly) is provided. Thesystem includes a dome having an aperture configured to surround aninjector assembly for a combustor. The dome having a front panelradially extending from the aperture and have a first cavity thatincludes a series of ducts. A first duct of the series of ducts isconfigured to receive airflow into the first cavity from a compressor,and a second set of ducts of the series of ducts and a third duct of theseries of ducts are configured to direct airflow to the combustor fromthe first cavity. The third duct having a larger diameter than thesecond set of ducts.

Optionally, the first cavity extends along a circumference of a backsideof the front panel.

Optionally, the first cavity extends along a portion of a circumferenceof a backside of the front panel. Additionally or alternatively, avolume of the first cavity and the diameter of the third duct are basedon a target frequency indicative of a resonance. Additionally oralternatively, the dome includes a second cavity extending along aportion of a circumference of a backside of the front panel. The secondcavity further having the first duct, the second sets of ducts, and thethird duct. A volume of the first cavity is based on a first targetfrequency and a volume of the second cavity is based on a second targetfrequency.

Optionally, the second set of ducts are configured to direct an airflowto reduce a thermal temperature of the dome.

Optionally, the first cavity is configured to adjust an amount of airpressure delivered to the combustor.

In an embodiment, a method (e.g., for suppressing pressure pulsations ofa gas turbine assembly) is provided. The method includes providing adome having an aperture configured to surround an injector assembly fora combustor. The dome having a front panel extending radially from theaperture. The method includes coupling a first cavity to the frontpanel. The first cavity includes a series of ducts. A first duct isconfigured to receive airflow into the first cavity from the compressor.And a second set of ducts that are configured to direct an airflow toreduce a thermal temperature of the dome.

Optionally, the first cavity includes a third duct configured to directairflow to the combustor from the first cavity. The third duct has adiameter larger than the second set of ducts.

Optionally, the first cavity extends along a circumference of a backsideof the front panel.

Optionally, the first cavity extends along a portion of a circumferenceof a backside of the front panel.

Optionally, the method includes adjusting a volume of the first cavityand the diameter of the third duct based on a target frequencyindicative of a resonance.

Optionally, the second set of ducts are positioned about the third duct.

Optionally, the method includes coupling a second cavity to the firstcavity. The second cavity having a third duct configured to receiveairflow into the second cavity from the compressor and a fourth ductconfigured to direct airflow to a combustor. The fourth duct has adiameter larger than the second set of ducts. Additionally oralternatively, the third duct interconnects the first and secondcavities and is configured to direct airflow from the first cavity tothe second cavity. Additionally or alternatively, the front panel isangled to direct the airflow of the second set of ducts and the fourthduct away from the aperture.

In an embodiment, a system (e.g., gas turbine assembly) is provided. Thesystem includes a front panel radially extending from an aperture thatsurrounds an injector assembly of the gas turbine assembly. The frontpanel having first and second cavities with the first cavity having afirst set of ducts configured to receive airflow into the first cavityfrom the compressor. A second set of ducts configured to direct airflowto a combustor. The second cavity having a third duct configured toreceive airflow into the second cavity and a fourth duct configured todirect airflow to a combustor. The fourth duct having a diameter largerthan the second set of ducts.

Optionally, the third duct interconnects the first and second cavitiesand is configured to direct airflow from the first cavity to the secondcavity. Additionally or alternatively, the second set of ducts arepositioned about the fourth duct. Additionally or alternatively, thefront panel is angled to direct the airflow of the second set of ductsand the fourth duct away from the aperture.

As used herein, an element or step recited in the singular and proceededwith the word “a” or “an” should be understood as not excluding pluralof said elements or steps, unless such exclusion is explicitly stated.Furthermore, references to “one embodiment” of the presently describedsubject matter are not intended to be interpreted as excluding theexistence of additional embodiments that also incorporate the recitedfeatures. Moreover, unless explicitly stated to the contrary,embodiments “comprising” or “having” an element or a plurality ofelements having a particular property may include additional suchelements not having that property.

It is to be understood that the above description is intended to beillustrative, and not restrictive. For example, the above-describedembodiments (and/or aspects thereof) may be used in combination witheach other. In addition, many modifications may be made to adapt aparticular situation or material to the teachings of the subject matterset forth herein without departing from its scope. While the dimensionsand types of materials described herein are intended to define theparameters of the disclosed subject matter, they are by no meanslimiting and are exemplary embodiments. Many other embodiments will beapparent to those of skill in the art upon reviewing the abovedescription. The scope of the subject matter described herein should,therefore, be determined with reference to the appended claims, alongwith the full scope of equivalents to which such claims are entitled. Inthe appended claims, the terms “including” and “in which” are used asthe plain-English equivalents of the respective terms “comprising” and“wherein.” Moreover, in the following claims, the terms “first,”“second,” and “third,” etc. are used merely as labels, and are notintended to impose numerical requirements on their objects. Further, thelimitations of the following claims are not written inmeans-plus-function format and are not intended to be interpreted basedon 35 U.S.C. § 112(f), unless and until such claim limitations expresslyuse the phrase “means for” followed by a statement of function void offurther structure.

This written description uses examples to disclose several embodimentsof the subject matter set forth herein, including the best mode, andalso to enable a person of ordinary skill in the art to practice theembodiments of disclosed subject matter, including making and using thedevices or systems and performing the methods. The patentable scope ofthe subject matter described herein is defined by the claims, and mayinclude other examples that occur to those of ordinary skill in the art.Such other examples are intended to be within the scope of the claims ifthey have structural elements that do not differ from the literallanguage of the claims, or if they include equivalent structuralelements with insubstantial differences from the literal languages ofthe claims.

What is claimed is:
 1. A method comprising: providing a dome having (a)an aperture configured to surround a combustor injector assembly, (b) afront panel extending radially from the aperture, and (c) a lip memberextending from the aperture, a gap being defined between the front paneland the lip member and a radially outer end of the gap being open to acombustor combustion-chamber; coupling a first cavity to the frontpanel, wherein the first cavity includes a series of ducts, wherein afirst duct of the series of ducts receives airflow into the first cavityfrom a compressor, and a set of second ducts directing the airflow fromthe first cavity into the gap to reduce a thermal temperature of thedome; coupling a second cavity to the first cavity, the second cavityhaving a third duct receiving airflow into the second cavity from thecompressor, and a fourth duct radially outward from the set of secondducts and directing the airflow from the second cavity to said combustorcombustion-chamber, providing the fourth duct with a diameter largerthan a diameter of each duct of the set of second ducts; and angling thelip member to direct the airflow from the first cavity away from theaperture, wherein the front panel provides a downstream wall of thefirst cavity and the second cavity, the first cavity is between aportion of the second cavity and the front panel.
 2. The method of claim1, wherein the first cavity extends along a circumference of a backsideof the front panel.
 3. The method of claim 1, wherein the first cavityextends along a portion of a circumference of a backside of the frontpanel.
 4. The method of claim 1, further comprising adjusting a volumeof the first cavity, a diameter of the first duct, and the diameter ofeach duct of the set of second ducts based on a target frequencyindicative of a resonance.
 5. The method of claim 1, wherein the frontpanel is angled to direct the airflow of the set of second ducts and thefourth duct away from the aperture.